untreated
adjective
un·treat·ed
ˌən-ˈtrē-təd 
: not treated
untreated wastewater
especially
: not improved or controlled medically
an untreated case of pneumonia
untreated diabetic patients
Examples of untreated in a Sentence
untreated wool
Recent Examples on the Web
Erythromycin eye ointment protects against gonorrhea that can be contracted during birth and potentially cause blindness if untreated.
—
CBS News, 21 Mar. 2026
The South Bay International Wastewater Treatment Plant, also operated by the IBWC, processed less than 25 million gallons per day throughout the heatwave — leaving a significant volume of untreated wastewater flowing through unchecked.
—Walker Armstrong, San Diego Union-Tribune, 21 Mar. 2026
If left untreated, Max’s condition could lead to MDS (myelodysplastic syndrome), a type of blood cancer, and from there possibly into acute myeloid leukemia (AML).
—Melissa Rudy, FOXNews.com, 20 Mar. 2026
Restrictions remain in place for areas closest to the site of the Potomac Interceptor rupture, which released more than 240 million gallons of untreated sewage into the river.
—Mathew Schumer, Baltimore Sun, 18 Mar. 2026
See All Example Sentences for untreated
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CBS News, 21 Mar. 2026
The South Bay International Wastewater Treatment Plant, also operated by the IBWC, processed less than 25 million gallons per day throughout the heatwave — leaving a significant volume of untreated wastewater flowing through unchecked.
—Walker Armstrong, San Diego Union-Tribune, 21 Mar. 2026
If left untreated, Max’s condition could lead to MDS (myelodysplastic syndrome), a type of blood cancer, and from there possibly into acute myeloid leukemia (AML).
—Melissa Rudy, FOXNews.com, 20 Mar. 2026
Restrictions remain in place for areas closest to the site of the Potomac Interceptor rupture, which released more than 240 million gallons of untreated sewage into the river.
—Mathew Schumer, Baltimore Sun, 18 Mar. 2026
See All Example Sentences for untreated
Cite this Entry
“Untreated.” Merriam-Webster.com Dictionary, Merriam-Webster, https://www.merriam-webster.com/dictionary/untreated. Accessed 28 Mar. 2026.
Copy CitationMedical Definition
untreated
adjective
un·treat·ed
-ˈtrēt-əd
: not subjected to treatment
an untreated disease
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